New battery could charge phone in one minute

By Laura Onita

Published Tuesday, April 7, 2015

A battery made from aluminium that can fully recharge a phone in a minute has been invented by US researchers.

The scientists from Stanford University said it can replace the lithium models traditionally found in laptops and mobile phones that take a long time to charge and it was both greener and safer as it was less prone to catching fire.

Publishing the findings in the journal Nature, Hongjie Dai, a professor of chemistry, hailed it as a breakthrough in battery technology that went further than previous attempts using aluminium.

Mr Dai said: “We have developed a rechargeable aluminium battery that may replace existing storage devices, such as alkaline batteries, which are bad for the environment, and lithium-ion batteries, which occasionally burst into flames.

“Our new battery won't catch fire, even if you drill through it.”

Although the voltage is higher than anyone has achieved with aluminium according to the researchers – about 2V – the battery has only half the voltage of lithium-ion batteries – usually 3.7V or 4.2V.

Scientists have struggled in the past to make commercially viable aluminium-ion batteries due to the materials that were not capable of generating enough volts of electricity after repeated cycles of charging and discharging.

But the prototype was said to be more durable, withstanding more than 7,500 cycles without any loss of capacity and surpassing previous aluminium batteries which died after just 100 charge-discharge cycles. By comparison, a typical lithium-ion battery lasts about 1,000 cycles.

“This was the first time an ultra-fast aluminium-ion battery was constructed with stability over thousands of cycles,” the study said.

The new battery has “unprecedented charging times” and it is also flexible so it can be used in new folding devices.

Ming Gong, co-author of the paper and graduate student, said: “Another feature of the aluminium battery is flexibility. You can bend it and fold it, so it has the potential for use in flexible electronic devices. Aluminium is also a cheaper metal than lithium.”

In addition to small electronic devices, aluminium batteries could be used to store renewable energy on the electrical grid, Dai said.